Generally, a refrigerator is a home appliance which stores food at a low temperature in a storage space formed therein to be opened and closed by a door. To this end, the refrigerator is formed to cool an inside of the storage space using cooling air generated through heat exchange with a refrigerant circulated in a refrigeration cycle, and thus to keep the stored food in an optimum state.
In the refrigerator, a temperature in the refrigerator is maintained at a set temperature to keep the food stored therein in the optimum state according to a use characteristic.
To this end, electric power should be always supplied to the refrigerator, and a compressor, a fan, a damper and so on should be driven to check a temperature state in the refrigerator and to maintain the set temperature.
Meanwhile, when a power outage occurs while the refrigerator is being used, an operation of all of electronic components in the refrigerator including the compressor, the fan, the damper and so on is stopped, and thus a cooling operation in the refrigerator may not be performed. When a power outage state becomes longer or a door of the refrigerator is opened and closed, the temperature in the refrigerator is increased, and thus there are some problems that, for example, the stored food may spoil.
To prepare for the power outage state, there has been developed a refrigerator in which a cold storage material is provided therein, and an inside of the refrigerator is cooled using the cold storage material while a refrigeration cycle is not driven.
However, such a refrigerator may temporarily maintain cooling performance, but the cooling performance of the cold storage material is continuously lowered, and thus cooling efficiency is degraded.